Mold for extruding an aluminum seat of a heat sink and a method for making the same

ABSTRACT

An aluminum seat of a heat sink is made by placing a fixed amount of aluminum material into a forming slot of a lower die to undergo one-time extrusion by a punch of an upper die. A plurality of indentations are longitudinally disposed on an interior wall of the forming slot of the lower die, and the bottom of the forming slot is a closed end. When the fixed amount of aluminum material is distributed over the forming slot and the indentations during the extrusion, corresponding ribs are formed on an exterior wall of the aluminum seat of the heat sink after the dies are drawn off. Each rib facilitates firm insertion of fin units into the seat. The heat sink with radial fin units is produced from the aluminum seat and the fin units.

BACKGROUND OF THE INVENTION

(a) Field of the Invention

The present invention relates to a mold for extruding an aluminum seat of a heat sink and a method for making the same. More particularly, the invention relates to extruding a fixed amount of aluminum material into the aluminum seat with a plurality of ribs defined on an exterior wall thereof by one-time extrusion using an upper die and a lower die.

(b) Description of the Prior Art

A conventional heat sink comprises a plurality of fin units and an aluminum seat, wherein the fin units are radially and integrally structured on an exterior wall of the aluminum seat. However, the manufacturing process is complicated, and the manufacturing cost is high. Moreover, the conventional heat sink is bulky and the number of the fin units is unsatisfactory for efficiently dispersing heat.

Conventionally, the fin units are respectively soldered to the exterior wall of the aluminum seat. Obviously, the soldering is time-consuming and laborious, and the soldering even needs electroplating. The manufacturing process is not good for the environment and the completed product is inefficient in dispersing heat. While the aluminum material is directly trimmed into solid disks, the trimming is still time-consuming and laborious. Accordingly, it is not desirable to produce the heat sink in large numbers by the conventional means. Even worse, extra costs are required to treat the waste material.

The aluminum seat of the heat sink can be a hollow seat that has an appearance of a round shape, a square, a triangle, or other appropriate shapes. For the hollow seat, a seat end of the heat sink provides a closed plane for attaching to a heat source (CPU).

SUMMARY OF THE INVENTION

It is therefore the purpose of this invention to provide a mold for extruding an aluminum seat of a heat sink and a method for making the same, wherein a fixed amount of aluminum material is placed in a forming slot of a lower die. An upper die allows the fixed amount of aluminum material to be integrally formed into the aluminum seat of the heat sink by one-time extrusion. The lower die has a forming slot that includes a plurality of indentations longitudinally disposed on an interior wall of the forming slot. A slot bottom of the forming slot is a closed end. The fixed amount of aluminum material is distributed over the forming slot and the indentations by extrusion from the upper die. The aluminum seat of the heat sink with a plurality of ribs formed on an exterior wall thereof is obtained after the dies are withdrawn. Accordingly, the production of the present invention is efficient, and the fixed amount of the aluminum material is just prepared for the one-time extrusion. Therefore, no redundant waste will be caused and the cost is reduced. Moreover, the amount of the material can be appropriately controlled.

A further object of the present invention is to provide a mold for extruding an aluminum seat of a heat sink, wherein an upper die and a lower die are installed on a processing machine such as hydraulic equipment or a press machine. The lower die has a forming slot, which may adopt a round shape, a square, a triangle, or other suitable shapes, including a hollow formation and a closed plane. A plurality of indentations are longitudinally disposed on an interior wall of the forming slot by wire cutting machining or electrical discharge machining. Accordingly, when the fixed amount of the aluminum material is pressed by the upper die after it is placed in the forming slot, the aluminum material is distributed over the forming slot and the indentations. Finally, the aluminum seat of the heat sink with a plurality of ribs formed on an exterior wall thereof is obtained after the dies are withdrawn.

A further object of the present invention is to provide a mold for extruding an aluminum seat of a heat sink, wherein a plurality of indentations are longitudinally disposed on an interior wall of the forming slot of a lower die. The indentations include first indentations and second indentations alternating with each other. Then, the correspondingly formed aluminum seat of the heat sink further provides first ribs and second ribs for allowing the insertion of the fin units, and a firm buckling is achieved by a pressing using a punching machine.

A further object of the present invention is to provide a mold for extruding an aluminum seat of a heat sink, wherein, the slot bottom of the forming slot of the lower die is smaller than a slot opening, thereby allowing the forming slot to be formed into a taper contour. Accordingly, the dies of the mold can be drawn off efficiently.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of the mold of the present application, showing an aluminum material being placed on a forming slot of a lower die of a processing machine;

FIG. 2 is a schematic view showing the aluminum material undergoing the extrusion according to the present invention;

FIG. 3 is a schematic view showing dies of a mold of the present invention being drawn off after extrusion;

FIG. 4 is a schematic view showing an aluminum seat of a heat sink being drawn from the forming slot of the lower die;

FIG. 5 is an enlarged view of the lower die;

FIG. 6 is a cross-sectional view of the lower die;

FIG. 7 is a perspective view of the aluminum seat of the heat sink formed by the mold of the present application;

FIG. 8 is a top view of FIG. 7;

FIG. 9 is a cross-sectional view of FIG. 7;

FIG. 10 is a perspective view of a square aluminum material adopted by the present invention;

FIG. 11 is a schematic view showing a square aluminum seat of the heat sink formed by the mold of the present application;

FIG. 12 is a top view of FIG. 11;

FIG. 13 is a cross-sectional view of FIG. 11;

FIG. 14 is a schematic view showing the aluminum seat of the heat sink being buckled with a plurality of fin units; and

FIG. 15 is a schematic view showing the square aluminum seat of the heat sink being buckled with a plurality of fin units.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIGS. 1 to 4 show a method for extruding an aluminum seat of a heat sink. A fixed amount of aluminum material 10 is provided and placed in a forming slot 11 of a lower die 1. A punch 21 of an upper die 2 allows the fixed amount of aluminum material 10 to be integrally formed into the aluminum seat 100 of the heat sink by one-time extrusion. Referring to FIGS. 5 and 6, the forming slot 11 of the lower die 1 includes a plurality of like or unlike indentations 111, 112 longitudinally defined on an interior wall of the forming slot 11. A slot bottom of the forming slot 11 is a closed end. First, the fixed amount of aluminum material 10 is placed in the forming slot 11 in accordance with a correspondent shape. Then, the aluminum material 10 is pressed by the upper die 2. The aluminum material 10 is accordingly distributed over the forming slot 11 and the indentations 111, 112. The aluminum seat 100 (as shown in FIGS. 7 to 9) of the heat sink with a plurality of ribs 101, 102 correspondingly formed on an exterior wall thereof is obtained after the dies are drawn off. Herein, the production of the present invention is efficient, and a fixed amount of the aluminum material 10 is prepared for the one-time extrusion. Therefore, no redundant waste will be caused and the cost is reduced. Moreover, the amount of the material can be appropriately controlled.

The punch 21 of the upper die 2 has a dimension smaller than the forming slot 11 of the lower die 1. After extrusion, the aluminum seat 100 of the heat sink produced has a certain thickness. The thickness of the aluminum seat 100 varies with the distance between the punch 21 and the forming slot 11.

The mold for extruding the aluminum seat of the heat sink further utilizes a processing machine 3, such as hydraulic equipment or a press machine installed with an upper die 2 and a lower die 1. The upper die 2 has a punch 21 appropriately formed. The lower die 1 has a forming slot 11 that includes a bottom part with a closed end that may adopt a round shape, a square, a triangle, or other suitable structure. Moreover, a plurality of indentations 111, 112 are longitudinally disposed on an interior wall of the forming slot 11 by wire cutting machining or electrical discharge machining. Accordingly, the fixed amount of aluminum material 10 can be placed and swiftly extruded to produce the aluminum seat 100 of the heat sink.

Referring to FIG. 7, the indentations formed on the interior wall of the forming slot 11 of the lower die 1 include first indentations 111 and second indentations 112 alternating with each other. As a result, first ribs 101 and second ribs 102 are correspondingly formed on the aluminum seat 100 of the heat sink. Wherein, the first ribs 101 allow the insertion of the fin units 200, and the second ribs 102 are pressed by the press machine and subjected to deformation. Accordingly, the ribs and the fin units 200 cooperatively create a firm buckling effect (as shown in FIG. 14). In the present invention, the forming slot 11 of the lower die 1 is not limited to one that includes the first indentations 111 and the second indentations 112 alternating with each other. Namely, the indentations can be structured to have the same formation and arranged adjacently; that is, the indentations do not have to be structured by two different formations. Also, the ribs formed on the aluminum seat of the heat sink have a corresponding formation; that is, the ribs do not have to be formed in two unlike formations.

Referring to FIGS. 8 and 9, the slot bottom 113 of the forming slot 11 of the lower die 1 is smaller than the slot opening 114, thereby allowing the forming slot 11 to be formed into a taper contour with the internal wall slanted at an angle θ. Accordingly, the dies can be drawn off efficiently, and the completed aluminum seat 100 of the heat sink can be taken out easily. Similarly, an upper opening of the aluminum seat 100 of the heat sink is larger than its seat end, and the aluminum seat 100 has the same taper contour with its wall slanted at an angle θ.

The aluminum material 10 is formed by trimming a fixed length of a round aluminum bar as shown in FIG. 1. Accordingly, the fixed amount of the round aluminum material 10 is placed in the forming slot 11 that is also built in the round shape for one-time extrusion. Referring to FIG. 10, similarly, the aluminum material 10 a is formed by trimming a fixed amount of a bar-typed aluminum material with a square cross-section. A piece of square aluminum material 10 a is placed in the forming slot that is also built into the shape of square for extruding a square aluminum seat 100 a of the heat sink (as shown in FIGS. 11 to 13). Obviously, it is unnecessary to limit the formation of the forming slot of the lower die to the round shape, the square, the triangle, or other shapes.

Referring to FIG. 14, when the aluminum seat 100 of the heat sink is inserted by the fin units 200, the press machine punches the second ribs 102, so that the second ribs 102 are deformed to cause a firm buckling effect between the fin units 200 and the aluminum seat 100 of the heat sink. Such buckling means ensures that each of the fin units 200 is firmly engaged to the seat 100. A similar buckling effect also exists in the square aluminum seat 100 a of the heat sink and the fin units 200 a in FIG. 15.

No matter which aluminum seat, referred by the number 100 or 100 a, is adopted, at least one depression 103 or pillar 104 a is formed on a part of an interior of the aluminum seat in accordance with the practical formation of the aluminum seat. Accordingly, the depression 103 or the pillar 104 facilitates a cooperative combination or a fastening effect with other components. Similarly, when at least one depression 103 or pillar 104 a is formed on the aluminum seat 100 or 100 a of the heat sink, a corresponding protrudent rib 211 (as shown in FIG. 1) or groove (not shown) is disposed on the punch of the upper die 2. Accordingly, when the aluminum seat 100 or 100 a is completed by the extrusion, the depression 103 or the pillar 104 a is correspondingly formed.

Preferably, the dimension or the appearance of the fin units 200 or 200 a is not limited while the fin units are inserted to the aluminum seat 100 or 100 a.

While the present invention has been described with regard to particular embodiments, it is recognized that further variations, alternatives and modifications may be apparent to any person skilled in the art and be devised without departing from the scope of the present invention and the inventive concept embodied therein. 

What is claimed is:
 1. A method for making an aluminum seat of a heat sink, comprising the steps of: providing and placing a fixed amount of aluminum material in a forming slot of a lower die, wherein said forming slot of said lower die includes a plurality of like or unlike indentations longitudinally defined on an interior wall of said forming slot, and a slot bottom of said forming slot is a closed end; pressing said aluminum material by a punch of an upper die, whereby distributing said aluminum material over said forming slot and said indentations; and withdrawing the dies to obtain an aluminum seat of a heat sink with a plurality of ribs formed on an exterior wall thereof.
 2. The method as claimed in claim 1, wherein said upper die and said lower die allow said fixed amount of aluminum material to be integrally formed into said aluminum seat by one-time extrusion.
 3. The method as claimed in claim 1, wherein said fixed amount of aluminum material is formed in a shape corresponding to that of said forming slot.
 4. The method as claimed in claim 1, wherein said aluminum material is formed by trimming a fixed length of a round aluminum bar.
 5. The method as claimed in claim 1, wherein said aluminum material is formed by trimming a fixed length of an aluminum bar with a square cross-section.
 6. A mold for extruding an aluminum seat of a heat sink including an upper die and a lower die installed on a processing machine; said upper die having a punch; said lower die having a forming slot that includes a slot bottom with a closed end, and a plurality of indentations longitudinally disposed on an interior wall of said forming slot, wherein the punch of said upper die extends into said forming slot of said lower die when the upper die and the lower die close in on each other.
 7. The mold as claimed in claim 6, said processing machine includes hydraulic equipment or a press machine.
 8. The mold claimed in claim 6, wherein said indentations formed on said interior wall of said forming slot of said lower die include first indentations and second indentations alternating with each other.
 9. The mold as claimed in claim 6, wherein the slot bottom of said forming slot of said lower die is smaller than a slot opening, so that said forming slot has a taper contour.
 10. The mold as claimed in claim 6, wherein, said forming slot of said lower die has a round, a square, or a triangular cross-section.
 11. The mold as claimed in claim 6, wherein said punch of said upper die includes at least one longitudinal protrudent rib.
 12. The mold as claimed in claim 6, wherein said punch of said upper die includes at least one longitudinal groove. 